The writer of a Bohemian poem on the legend of St. Catherine’s betrothal to Christ, written about 1355, appears to have been, in one part, inspired by the glowing adornment of the Wenceslaus chapel in the cathedral of St. Veit. The poet gives an enthusiastic description of the gorgeous ornamentation of the mystic, imaginary temple in which the betrothal takes place. The pavement is of aquamarine beryl, the walls are studded with diamonds in golden settings, the framework of the windows is alternately of emerald or of sapphire, and the window-panes are not of stained glass, but of precious or semi-precious stones. Some of these are not ill fitted for this use, the transparency of rubies, amethysts, spinels, jacinths, garnets, and similar stones, admitting quite sufficient light; but others mentioned here, such as turquoises, chalcedonys and jaspers, would permit but a dim ray of light to traverse their opaque or semi-opaque substance. It has been conjectured by some that the poet drew his material from the account of the temple of the Holy Grail in the old German legend, probably through a Bohemian version; but as he omits in his enumeration twelve of the stones given in the Grail legend, and adds a number of others, diamond, turquoise, chalcedony, garnet, etc., this literary source is not fully satisfactory. Rather might it be believed that the splendid decoration of the Wenceslaus chapel and of the Karlstein Castle suggested the vision wrought out by the Bohemian poet, especially as among the stones he mentions which are not in the Grail legend, we have the garnet, so eminently a product of Bohemia.[536] A peculiar and very interesting facetted diamond of 6³⁄₃₂ carats displays alternate black and white facets and presents the appearance of a clearly defined Greek cross in black outline when viewed by transmitted light. The original crystal, which came from Brazil and weighed 10½ carats, was an octahedron and was of a jet black hue. The expectation was that the result of its cutting would be the production of a black brilliant, but when one of the points of the octahedron had been removed to form the table, it became evident that the black tint was only superficial, the body of the crystal being white. This peculiarity was then utilized by leaving some of the natural black faces of the crystal. This diamond was found to be of excessive hardness, rendering the task of cutting it an exceedingly arduous one. It is now in the possession of one of the Royal Household of Siam.[537]